Motion of an object of interest, such as a cell, has a variable velocity
that can be varied on a cell-by-cell basis. Cell velocity is controlled
in one example by packing cells into a capillary tube, or any other
linear substrate that provides optically equivalent 360 degree viewing
access, so that the cells are stationary within the capillary tube, but
the capillary tube is translated and rotated mechanically through a
variable motion optical tomography reconstruction cylinder. The capillary
tube motion may advantageously be controlled in a start-and-stop fashion
and translated and rotated at any velocity for any motion interval, under
the control of a computer program. As such, there are several
configurations of the optical tomography system that take advantage of
this controlled motion capability. Additionally, the use of polarization
filters and phase plates to reduce light scatter and diffraction
background noise is described.